1. Field of the Invention
The present invention relates to a lampholder.
2. Description of the Related Art
As shown in FIG. 9, a conventional lampholder includes a body 47, a female screw shell 48, a central contact spring 49, a cover 50, power terminal boards 52a, 52b, and lead wires 53a, 53b. The body 47 is made of insulating resin or ceramic and is in the form of a cylinder with the bottom. The female screw shell 48 is made of metal and connected electrically to a shell (not shown), e.g., of an E-type cap (not shown) for a lamp (not shown). Similarly, the central contact spring 49 is made of metal and connected electrically to an eyelet (not shown) of the cap. The cover 50 is made of insulating resin or ceramic and provided at the end of the body 47. The power terminal boards 52a, 52b are fastened on the inner surface of the cover 50 with a pair of screws 51 (one of them is not shown). The lead wires 53a, 53b are connected electrically to the power terminal boards 52a, 52b. 
The body 47 and the cover 50 are connected mechanically with two screws 54a, 54b. One screw 54a mechanically connects the body 47 and the female screw shell 48, and also electrically connects the female screw shell 48 and the power terminal board 52a. The other screw 54b mechanically connects the body 47 and the central contact spring 49, and also electrically connects the central contact spring 49 and the power terminal board 52b. 
A screw 55 is used to adjust the amount of movement of the central contact spring 49 when the cap is inserted. The screw 55 prevents the contact failure between the central contact spring 49 and the eyelet resulting from unnecessary movement of the central contact spring 49 toward the cover 50.
However, in the conventional lampholder, many screws or the like are necessary to fasten each part together, particularly, to fasten the component of resin or ceramic, such as the body 47, and that of metal, such as the female screw shell 48. This requires the steps of tightening those screws as well. In other words, the parts are increased and the process is complicated, which in turn increases the cost and reduces the productivity.
Therefore, with the foregoing in mind, it is an object of the present invention to provide a lampholder that can achieve the reduction of cost and the improvement of productivity by reducing the parts and simplifying the process.
A lampholder of the present invention for receiving a lamp cap includes a body, a receiving portion provided in the body and to be connected to the cap, and a lead wire connected to the receiving portion. The receiving portion is made of conductive resin.
Unlike a conventional lampholder, this configuration eliminates the need to fasten the component of resin or ceramic, such as a body, and that of metal, such as a female screw shell, together. Therefore, many screws or the like are not necessary. As a result, the parts can be reduced and the steps of tightening the screws or the like can be omitted. Thus, the reduction of cost as well as the improvement of productivity can be achieved.
These and other advantages of the present invention will become apparent to those skilled in the art upon reading and understanding the following detailed description with reference to the accompanying figures.